1. Field of the Invention
The present invention is directed in general to the field of information processing. In one aspect, the present invention relates to a system and method for canceling interference in single antenna systems used in space division multiple access systems.
2. Description of the Related Art
Wireless communication systems transmit and receive signals within a designated portion of the electromagnetic frequency spectrum. However, the capacity of the electromagnetic frequency spectrum is limited. Thus, there is a need to improve the efficiency of spectrum utilization as the demand for wireless communication systems continues to expand.
Increasingly dense network coverage causes base stations to generate increasingly high levels of co-channel interference within the network. The effects of co-channel interference can be reduced by applying a class of algorithms known as Single Antenna Interference Cancellation (SAIC). Unlike Multiple Input Multiple Output (MIMO) systems, SAIC algorithms do not require the presence of multiple antennas on the mobile unit or the base station to reduce co-channel effects.
SAIC algorithms create relatively high computational requirements under the constraint of low latency. This is particularly true when incorporating the often-overlooked requirements associated with synchronization. During SAIC synchronization, proper delay estimation typically requires iterative computations across multiple SAIC delay values to perform initial synchronization. Furthermore, it is necessary to compute matrix inverses based upon minimum mean-square error (MMSE) formulations of the SAIC calculations. In addition to computational demands, SAIC techniques also generally require large amounts of memory.
As will be understood by those of skill in the art, many subscriber units, such as handheld mobile phones, have limited available memory. In addition, such devices have significant limitations with regard to size and power consumption. Accordingly, there is a need for an improved system and method for providing SAIC calculations for such mobile devices.
It will be appreciated that for simplicity and clarity of illustration, elements illustrated in the drawings have not necessarily been drawn to scale. Furthermore, where considered appropriate, reference numerals have been repeated among the drawings to represent corresponding or analogous elements.